[Psycho_Bunny]

People who assume to know whether we are "alone" or not, haven't the slightest capability of truly understanding how large the universe is, how much of it there is, and how limited human understanding is.

I've always found a persons presumption of "knowing" whether or not there is life elsewhere a bit akin to "knowing" what God's thinking right now: frankly, no one has a clue.  Sure, you can take a guess - and you might even be right - but, you can't prove it.

Never tie yourself to an absolute uncertainty; at best, you'll just look goofy.

[Exnihilo]

I don't think anyone has made any claims to knowledge.